UNSC: Bravo Squad
The queens are a variant and not a stage of the Xenomorph lifecycle. A Queen is a large Xenomorph that serves as the mother and leader of a xenomorph hive. Her appearance differs from that of a Drone, with a pair of extra arms and a large head crest. She is the largest, strongest of the knwon forms of the Xenomorph.
The Queen’ most prominent physical trait is its large, texturized, crown-like carapace, from which the soft spot of its head and its face can retreat into similar to a turtle. This great carapace is of disproportional size when compared to the rest of the Queen’s very large body. It also has double-jointed hind legs, two sets of spikes on it’s back, six digit hands – with the third finger being much longer than the others and its forearms – and chest also featuring some form of carapace. It has a much smaller set of arms on the center of its chest that have unknown purposes. Its tail is extremely long and segmented, with a blade-like tip. It’s overall color is of a greyish-green tone.
The queen is created from the Royal Facehugger. The facehugger when creating a queen appear to search for the best physically or the most hardest to catch.
Queens are very intelligent and have been shown to know how to operate machines and somewhat understand humans (actions, not speech). It should be said though that all Xenomorphs have shown intelligence in some respects, namely observation learning but it is known that Queens are superior. In Operation: Ant Farm the Queen had her Warriors back off after Hess threatened her eggs with a flamethrower, though Hess later killed the eggs anyway after one opened, presumably due to the belief that either the Queen did it or that a facehugger wouldn’t be restrained by the Queen and would attack Alpha Squad.
They can engage in combat, but usually remain stationary, letting the Praetorians (or drones and warriors, if none have developed yet), do their dirty work while they direct the hive and lay the eggs. A Queen can disconnect from its egg sack by pulling its tail out as seen in Operation: Spelunker. A Queen is much more intelligent than a normal Xenomorph, displaying traits of wrath and vengeance beyond any purely instinctual behavior as shown in Operation: Ant Farm. A Queen, despite her size ratio compared to other Xenomorphs, can sustain quite a bit of gunfire before having to retreat. Due to this, once outside of her larvae facility, a Queen can destroy most prey within seconds. A Queen’s size is massive, much larger than other variations of Xenomorph. The Queen is very fast for her size and can inflict massive amounts of damage, making her a very formidable opponent.